鋁合金熱擠伸之製程參數與再結晶行為關係之研究

Studies on the Relationship between Recrystallization Behaviour and Process Parameters of An Aluminiun Alloy in Hot Extrusion

李榮顯(Rong Shean Lee) ； 林煥章(Huan Chang Lin)

《鑛冶：中國鑛冶工程學會會刊》 36卷1期 (1992/03) Pp. 151-160

https://doi.org/10.30069/MM.199203_36(1).0012

摘要

本文目的在研究鋁合金熱擠伸製程中之製程參數與再結晶行為之關係。本文中以熱偶合上界限法分析圓棒之平模熱擠伸製程之出口溫度及應變率分布，並將其表示成含溫度與應變率之Zener-Hollomon參數Z。對於鋁合金6061鑄態材，以鍛壓實驗法求材料常數，供作熱擠伸分析資料之所需。以熱擠伸實驗，觀察材料流動歷程及產品之再結晶反應，做為建立製程參數與冶金現象關係之依據。研究結果顯示：擠伸產品之再結晶厚度隨Z參數值增加而變薄；再結晶晶粒直徑隨Z參數值增加而變細，出口溫度過高，易導致粗大再結晶晶粒之發生。最後亦歸納出得到良好擠製品顯微組織之可行方案。

並列摘要

The purpose of this paper is to investigate the relationship between the process parameters and the recrystallization behaviours in the hot extrusion process for an aluminium alloy. In this study, the thermal-coupled upper bound method was applied to predict the strain rate distribution and the temperature distribution in the hot extrusion of rod. The recrystallization depth and the grain size were represented by the Zener-Hollomon parameter. The effects of the Zener-Hollomon parameter on the recrystallization behaviours were studied. The grain size of peripheral recrystallization and its thickness were measured so that the quantitative relationship between the process parameters and the characteristics of recrystallization can be established. The results of this study show that the grain size of recrystallization and the thickness of recrystallized portion decrease with the increasing value of Zener-Hollomon parameter. The coarse grain of recrystallization occurs when the exit temperature of extrudate is too high. Finally, the approaches to obtain good microstructure of extrudate are suggested.